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Ian Romanick 20a067a837 spir-v: Mark floating point comparisons exact
OpenGL GLSL, OpenGL ARB assembly shaders, and DX9 are pretty loose about
the behavior in the presence of NaNs.  Many GPUs that implement these
specifications do not even have a representation of NaN.  However,
OpenCL and Vulkan SPIR-V are not so lax.  Both actually have some
required behavior in the presence of NaN, and, of the two, OpenCL is the
most strict.

For years we have implemented SPIR-V by using the same comparison
opcodes as we use for OpenGL GLSL and OpenGL assembly shaders.  This has
repeatedly caused problems where an optimization that is valid in the
NaN-relaxed world is not valid in Vulkan or OpenCL.  To fix this, set
the "exact" flag on comparisons instructions generated from SPIR-V.
This will block optimizations that may have different NaN behavior.

v2: Set the exact flag in the nir_builder, not in the vtn_builder.

v3: Add an assertion in vtn_handle_constant that the exact flag wasn't
set (because it's ignored).  Rebase on 80163bbec3 ("nir/vtn: Support
OpOrdered and OpUnordered opcodes").  Mark the NIR generated for those
opcodes as exact as well.

v4: s/unused_exact/exact/ in a couple places, and assert that exact has
the expected value (true in one place, false in the other).  Suggested
by Caio.

Closes: #3345
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Tested-by: Danylo Piliaiev <danylo.piliaiev@globallogic.com>
Fixes: 8513b12590 ("nir/opt_if: split ALU from Phi more aggressively")

This commit doesn't really fix anything in 8513b12590.  However,
without 8513b12590, a regression is triggered in RADV on No Man's
Sky.  I want to ensure that this change is only applied on top of
8513b12590, and Fixes: seems the safest way to do that.

No shader-db changes on any Intel platform.  This only affects SPIR-V,
and we have no OpenGL SPIR-V shaders in shader-db.

124 shaders in Shadow of the Tomb Raider (Steam "native") were hurt by 1
spill and 1 fill each.

All Intel platforms had similar results. (Tiger Lake shown)
Instructions in all programs: 155668276 -> 155685764 (+0.0%)

SENDs in all programs: 6474570 -> 6474570 (+0.0%)

Loops in all programs: 35271 -> 35271 (+0.0%)

Cycles in all programs: 3198055373 -> 3198628031 (+0.0%)

Spills in all programs: 231522 -> 231646 (+0.1%)

Fills in all programs: 347571 -> 347695 (+0.0%)

Vega
Totals:
SGPRs: 20955712 -> 20956756 (+0.00%); split: -0.02%, +0.03%
VGPRs: 13476920 -> 13473132 (-0.03%); split: -0.07%, +0.04%
CodeSize: 613371940 -> 613339348 (-0.01%); split: -0.06%, +0.05%
MaxWaves: 3111886 -> 3112481 (+0.02%); split: +0.02%, -0.00%
Instrs: 120723785 -> 120746991 (+0.02%); split: -0.04%, +0.06%
Cycles: 626658992 -> 626862708 (+0.03%); split: -0.05%, +0.08%
VMEM: 216330854 -> 216343196 (+0.01%); split: +0.04%, -0.04%
SMEM: 32079391 -> 32081972 (+0.01%); split: +0.05%, -0.04%
VClause: 2688784 -> 2688789 (+0.00%); split: -0.03%, +0.03%
SClause: 6554669 -> 6556251 (+0.02%); split: -0.01%, +0.03%
Copies: 5356667 -> 5353283 (-0.06%); split: -0.36%, +0.29%
Branches: 954466 -> 954716 (+0.03%); split: -0.01%, +0.04%
PreSGPRs: 9078300 -> 9081626 (+0.04%); split: -0.01%, +0.05%
PreVGPRs: 10972090 -> 10966576 (-0.05%); split: -0.06%, +0.01%

Totals from 48239 (12.08% of 399432) affected shaders:
SGPRs: 2713984 -> 2715028 (+0.04%); split: -0.16%, +0.19%
VGPRs: 1997804 -> 1994016 (-0.19%); split: -0.46%, +0.27%
CodeSize: 172094092 -> 172061500 (-0.02%); split: -0.21%, +0.19%
MaxWaves: 337327 -> 337922 (+0.18%); split: +0.20%, -0.02%
Instrs: 33053657 -> 33076863 (+0.07%); split: -0.15%, +0.22%
Cycles: 254961228 -> 255164944 (+0.08%); split: -0.12%, +0.20%
VMEM: 15165226 -> 15177568 (+0.08%); split: +0.59%, -0.51%
SMEM: 3304938 -> 3307519 (+0.08%); split: +0.49%, -0.41%
VClause: 766225 -> 766230 (+0.00%); split: -0.12%, +0.12%
SClause: 1332645 -> 1334227 (+0.12%); split: -0.04%, +0.16%
Copies: 2040651 -> 2037267 (-0.17%); split: -0.94%, +0.77%
Branches: 743668 -> 743918 (+0.03%); split: -0.01%, +0.05%
PreSGPRs: 1697667 -> 1700993 (+0.20%); split: -0.07%, +0.27%
PreVGPRs: 1718424 -> 1712910 (-0.32%); split: -0.39%, +0.07%

Polaris
Totals:
SGPRs: 21349172 -> 21354376 (+0.02%); split: -0.02%, +0.04%
VGPRs: 13690680 -> 13686920 (-0.03%); split: -0.07%, +0.04%
CodeSize: 613745824 -> 613704988 (-0.01%); split: -0.06%, +0.05%
MaxWaves: 2775012 -> 2775189 (+0.01%); split: +0.01%, -0.00%
Instrs: 120735079 -> 120756209 (+0.02%); split: -0.04%, +0.06%
Cycles: 627906100 -> 628076156 (+0.03%); split: -0.05%, +0.08%
VMEM: 216623065 -> 216641838 (+0.01%); split: +0.04%, -0.04%
SMEM: 32295618 -> 32299338 (+0.01%); split: +0.05%, -0.04%
VClause: 2711025 -> 2711141 (+0.00%); split: -0.03%, +0.04%
SClause: 6545185 -> 6546769 (+0.02%); split: -0.01%, +0.03%
Copies: 5387723 -> 5383249 (-0.08%); split: -0.37%, +0.29%
Branches: 953775 -> 953954 (+0.02%); split: -0.01%, +0.03%
PreSGPRs: 9148814 -> 9153211 (+0.05%); split: -0.01%, +0.06%
PreVGPRs: 11029429 -> 11023915 (-0.05%); split: -0.06%, +0.01%

Totals from 48239 (12.00% of 402052) affected shaders:

SGPRs: 2682056 -> 2687260 (+0.19%); split: -0.16%, +0.35%
VGPRs: 1994436 -> 1990676 (-0.19%); split: -0.46%, +0.27%
CodeSize: 170857060 -> 170816224 (-0.02%); split: -0.21%, +0.19%
MaxWaves: 295429 -> 295606 (+0.06%); split: +0.07%, -0.01%
Instrs: 32808802 -> 32829932 (+0.06%); split: -0.16%, +0.22%
Cycles: 254633252 -> 254803308 (+0.07%); split: -0.13%, +0.20%
VMEM: 14897934 -> 14916707 (+0.13%); split: +0.65%, -0.52%
SMEM: 3289726 -> 3293446 (+0.11%); split: +0.53%, -0.42%
VClause: 775318 -> 775434 (+0.01%); split: -0.11%, +0.13%
SClause: 1304867 -> 1306451 (+0.12%); split: -0.04%, +0.16%
Copies: 2026334 -> 2021860 (-0.22%); split: -0.99%, +0.77%
Branches: 742554 -> 742733 (+0.02%); split: -0.02%, +0.04%
PreSGPRs: 1690887 -> 1695284 (+0.26%); split: -0.07%, +0.33%
PreVGPRs: 1717709 -> 1712195 (-0.32%); split: -0.40%, +0.07%
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6358>
(cherry picked from commit 010e663cc3)
2021-01-06 09:31:35 -08:00
.appveyor appveyor: Use Python3. 2020-08-06 09:46:48 +00:00
.gitlab/issue_templates gitlab: ask for more detailed info about GPU 2020-08-20 11:56:19 +00:00
.gitlab-ci ci/deqp: Fix inverted meaning of DEQP_NO_SAVE_RESULTS. 2020-12-28 15:58:57 -08:00
bin android_stub: Update platform headers to include gralloc1.h. 2020-10-19 18:41:50 +00:00
build-support configure: commit test files 2017-10-16 16:32:43 -07:00
docs docs: Add sha256 sum for 20.3.2 2020-12-30 20:11:04 -08:00
doxygen doxygen: Plumb through gallium/ to automated documentation 2016-05-30 17:53:45 +01:00
include CL: update CL headers to 3.0 2020-11-06 17:02:54 +10:00
scons scons/windows: Support build with LLVM 11. 2020-10-23 17:17:01 -07:00
src spir-v: Mark floating point comparisons exact 2021-01-06 09:31:35 -08:00
subprojects meson: use github URL for wraps instead of completely unreliable wrapdb 2020-01-16 23:06:43 +00:00
.dir-locals.el dir-locals.el: Adds White Space support 2016-11-14 19:17:49 +02:00
.editorconfig docs: fixup indentation 2020-01-18 11:39:32 +01:00
.gitignore intel/tools: Add unit tests for assembler 2019-05-07 14:33:48 -07:00
.gitlab-ci.yml ci: Drop x86_build_old image 2020-12-07 09:20:39 -08:00
.mailmap .mailmap: add an alias for Andres Gomez 2020-04-30 14:33:20 +03:00
.pick_status.json spir-v: Mark floating point comparisons exact 2021-01-06 09:31:35 -08:00
.travis.yml travis: autodetect python version instead of hard-coding it 2019-12-21 20:23:08 +00:00
Android.common.mk tree-wide: fix deprecated GitLab URLs 2020-05-23 15:33:50 +00:00
Android.mk ac/llvm: handle static/shared llvm init separately 2020-08-17 10:47:41 +00:00
CleanSpec.mk CleanSpec.mk: Remove HOST_OUT_release 2018-08-02 15:42:40 -06:00
common.py scons: Print a deprecation warning about using scons on not windows 2019-10-24 18:33:50 +00:00
meson.build meson: Fix Clang microsoft-enum-value detection. 2020-12-07 09:17:50 -08:00
meson_options.txt meson: Don't add extra values to shader-cache 2020-11-24 22:08:17 -08:00
README.rst README: update references to internal docs 2020-06-13 10:42:01 +00:00
REVIEWERS REVIEWERS: add VMware reviewers 2019-10-18 16:42:40 +00:00
SConstruct tree-wide: fix deprecated GitLab URLs 2020-05-23 15:33:50 +00:00
VERSION Bump version for 20.3.2 release 2020-12-30 19:58:21 -08:00

`Mesa <https://mesa3d.org>`_ - The 3D Graphics Library
======================================================


Source
------

This repository lives at https://gitlab.freedesktop.org/mesa/mesa.
Other repositories are likely forks, and code found there is not supported.


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---------------

You can find more information in our documentation (`docs/install.rst
<https://mesa3d.org/install.html>`_), but the recommended way is to use
Meson (`docs/meson.rst <https://mesa3d.org/meson.html>`_):

.. code-block:: sh

  $ mkdir build
  $ cd build
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